We are conducting an epidemiological prostate cancer case-control study in Baltimore, Maryland. Participants will be African-American and Caucasian males who reside in Baltimore city and surrounding areas. The study is ongoing and will recruit 600 prostate cancer cases and 600 population-based controls. The cases are recruited at two Baltimore hospitals, the Veterans Affairs Medical Center and the University of Maryland Medical Center, over a period of 5 years. Cases will have pathologically confirmed prostate cancer. The population-based controls are identified through the Maryland Department of Motor Vehicle database, and are frequency-matched by age and race to cases. Enrollment of controls started concurrently with case accrual. The first 12 months of the study constituted a pilot study, during which we evaluated the recruitment procedures. The study involves the administration of two questionnaires and collection of blood from all study subjects. The two questionnaires consist of a main questionnaire and a supplemental questionnaire. The questionnaires evaluate family cancer history, tobacco use, medication, occupational history, socioeconomic status, and risk factors for prostate cancer. Fresh-frozen tumor specimens will be obtained from cancer patients if available. The study is supported by an epidemiological infrastructure that has been developed by our resource contractor at the University of Maryland for an ongoing lung cancer case-control study. We are recruiting the controls using a double eligibility criterion. Hence, population-based male controls will be eligible for both the prostate and lung study. To achieve an age and race matching of cases and controls in the prostate study, we will over-sample male controls in the lung study. Currently we are analyzing tissue and blood samples from the ongoing collection to identify differences in immune markers between African-American and Caucasian prostate cancer patients. We are also utilizing this resource to elucidate the mechanism(s) of tobacco smoke-induced metastatic prostate cancer. These efforts support research described under Z01 BC 010660.